Abstract: An improved drive lug and shaft through bore structure for use with a wobble plate compressor, the output of which is modulated in response to refrigeration requirements by varying the piston displacement to match the cooling requirement. The drive lug has a cylindrical body formed with a radially outer flat-sided wobble plate connection portion and a radially inner shank of reduced diameter separated by a radiused neck transition portion. A flared opening in the shaft bore receives the neck portion while means on its free end of the shank portion cooperate with the shaft securing the lug in the shaft bore so as to establish a clearance fit between the lug shank and the bore providing extended fatigue life together with ease of manufacture and assembly.